The current development towards truly mobile computing and networking has brought on the evolvement of various access technologies that also provide the users with access to service providing networks, such as the Internet, when they are outside their own home network. At present, wireless Internet access is typically based on either short-range wireless systems or mobile networks, or both.
Short-range wireless systems have a typical range of about one hundred meters or less. They often combine with systems wired to the Internet to provide communication over long distances. The category of short-range wireless systems includes wireless personal area networks (PANs) and wireless local area networks (WLANs). They have the common feature of operating in unlicensed portions of the radio spectrum, usually either in the 2.4 GHz Industrial, Scientific, and Medical (ISM) band or in the 5 GHz unlicensed band.
Wireless personal area networks use low cost, low power wireless devices that have a typical range of about ten meters. The best-known example of wireless personal area network technology is Bluetooth, which uses the 2.4 GHz ISM band. It provides a peak air link speed of one Mbps, and power consumption low enough for use in personal, portable electronics such as PDAs and mobile phones. Wireless local area networks generally operate at higher peak speeds of 10 to 100 Mbps and have a longer range, which requires greater power consumption.
Wireless LAN systems are typically extensions of a wired network, providing mobile users with wireless access to the wired network. Examples of wireless local area network technology include the IEEE 802.11a, which is designed for the 5 GHz unlicensed band, and uses orthogonal frequency division multiplexing (OFDM) to deliver up to 54 Mbps data rates; the 802.11b, which is designed for the 2.4 GHz ISM band and uses direct sequence spread spectrum (DSSS) to deliver up to 11 Mbps data rates; and the HIPERLAN Standard, which is designed to operate in the 5 GHz unlicensed band.
So-called multimode terminals are also becoming more and more common. Having the terminal provided with radio technologies according to multiple connectivity standards, the user can choose the network type most suitable in each case. However, a drawback related to the selection of the network through which the services are accessed is that the short-range wireless systems are available only locally in limited geographical areas, whereby a larger area, such as a city, may include a number of distinct service areas, each having its own characteristics according to the standard of connectivity used.
International Patent Application WO 02/01807 discloses a method for controlling and managing wireless network access in a wireless multi-standard environment. In this method, the terminal sequentially sends and/or scans for network polling information to determine whether the terminal is within range of a supported network. When one or more networks have been detected, a decision is made whether to connect to a detected network. The decision to connect to a particular network can be made on various grounds and the user may also be queried to decide whether to connect to a particular network. By a method like this, the network may be selected from those available at any given time, based on which is the best one in terms of certain “access criteria”, such as the quality of service, the data rate, or the price.
Another drawback of the above network environments relates to power consumption of the terminals. In order to detect supported networks in a communication environment comprising discrete and geographically confined access areas, the terminal should frequently search for the networks with which communications may be established. Since the terminal must frequently be in a power-consuming state, a lot of power is consumed for the search only.
Still another drawback of the current multimode network environment relates to the user-friendliness of the access management. When multiple radio technologies are integrated into one terminal, operating the different radio technologies becomes easily too technical for an average user. Therefore, new mechanisms are needed by which the technologies can be hidden from the user while simultaneously enabling easy access to local services when supported networks are available.
The present invention seeks to accomplish a solution by means of which the above drawbacks may be alleviated or eliminated.